Missing Value Imputation With Unsupervised Backpropagation

Many data mining and data analysis techniques operate on dense matrices or complete tables of data. Real-world data sets, however, often contain unknown values. Even many classification algorithms that are designed to operate with missing values still exhibit deteriorated accuracy. One approach to handling missing values is to fill in (impute) the missing values. In this paper, we present a technique for unsupervised learning called Unsupervised Backpropagation (UBP), which trains a multi-layer perceptron to fit to the manifold sampled by a set of observed point-vectors. We evaluate UBP with the task of imputing missing values in datasets, and show that UBP is able to predict missing values with significantly lower sum-squared error than other collaborative filtering and imputation techniques. We also demonstrate with 24 datasets and 9 supervised learning algorithms that classification accuracy is usually higher when randomly-withheld values are imputed using UBP, rather than with other methods

HOW DOES GENDER AFFECT THE ADOPTION OF AGRICULTURAL INNOVATIONS? THE CASE OF IMPROVED MAIZE TECHNOLOGY IN GHANA

Why do men and women adopt agricultural technologies at different rates? Evidence from Ghana suggests that gender-linked differences in the adoption of modern maize varieties and chemical fertilizer are not attributable to inherent characteristics of the technologies themselves but instead result from gender-linked differences in access to key inputs.Research and Development/Tech Change/Emerging Technologies,

An Optimization Model for Winery Capacity Use

An optimization model to sequence wine flow through the production process is developed. The model is formulated as a mixed integer program and accounts for winemaking specifications, market conditions, grape availability, and tank capacity. An empirical example is provided to demonstrate results and uses of the model.Agribusiness,

ACTA\u27s Abandoned Third-Party Liability Provisions and What They Mean for the Future

One of the most controversial aspects of the proposed Anti-Counterfeiting Trade Agreement (ACTA) was its requirement that signatories adopt a system of secondary liability akin to that which has developed in American law, but without the protections that have been carved out by statute and court. This white paper examines and explains the concept of secondary liability; the controversy surrounding its incorporation into ACTA; its exclusion from the ACTA draft leaked in August 2010, and the future of secondary liability expansion

An Extended Star Formation History for the Galactic Center from Hubble Space Telescope/NICMOS Observations

We present Hubble Space Telescope (HST) Near-Infrared Camera and Multiobject Spectrometer (NICMOS) observations as evidence that continuous star formation has created much of the central stellar cusp of the Galaxy. The data are the deepest ever obtained for a Galactic Center (GC) population, being $>$50% complete for \mnk$<19.3$, or initial stellar masses $\gtrsim$2 \Msun. We use Geneva and Padova stellar evolution models to produce synthetic luminosity functions for burst and continuous star formation scenarios, finding that the observations are fit best by continuous star formation at a rate that is consistent with the recent star formation activity that produced the three massive young clusters in the central 50 \pc. Further, it is not possible to fit the observations with ancient burst models, such as would be appropriate for an old population like that in Baade's Window or NGC6528

Derivative expansion of the renormalization group in O(N) scalar field theory

We apply a derivative expansion to the Legendre effective action flow equations of O(N) symmetric scalar field theory, making no other approximation. We calculate the critical exponents eta, nu, and omega at the both the leading and second order of the expansion, associated to the three dimensional Wilson-Fisher fixed points, at various values of N. In addition, we show how the derivative expansion reproduces exactly known results, at special values N=infinity,-2,-4, ... .Comment: 29 pages including 4 eps figures, uses LaTeX, epsfig, and latexsy

Extended treatment with MY-NEOVAX, personalized neoantigen-enhanced oncolytic viruses, for two end-stage cancer patients.

Neoantigen vaccines involving multi-peptides and poly-epitope-encoding RNA or DNA have undergone early phase clinical testing with modest reported antitumor effects [ 1]. The less-than-expected activity of these neoantigenic vaccines may correspond with the development of immune escape mechanisms. One permutation on neoantigen vaccines, which may counter or prevent these adaptive immune escape mechanisms, are 'personalized' oncolytic viruses that encode one or more tumor-specific transgenes. Herein, positive therapeutic effects for MY-NEOVAX™, personalized neoantigen-enhanced oncolytic adenoviruses, are described for two heavily pretreated end-stage patients, one with high-grade metastatic neuroendocrine carcinoma of the pancreas and the other with colorectal cancer metastatic to the brain, liver and lungs. To date, treatment benefit has exceeded 12 months without dose-limiting toxicities or related serious adverse events and with documented radiologic stabilization and improved performance status

Floodplain Succession and Soil Nitrogen Accumulation on a Salmon River in Southwestern Kamchatka

We documented riparian primary succession on an expansive floodplain (Kol River, Kamchatka, Russian Federation) that receives large nitrogen subsidies from spawning Pacific salmon. As is typical of primary succession, new alluvial deposits in the lower Kol floodplain were nitrogen poor (200 kg persulfate N/ha to 10 cm soil depth); however, nitrogen accumulated rapidly, and soils contained 1600 kg N/ha (to 10 cm + the litter layer) by 20 years. Soil nitrogen approached an asymptote at 2500 kg N/ha by 80 years. Nitrogen-fixing Alnus trees were a minor component of the forest community during the first 20 years of succession. However, salmon carcasses were a substantial nitrogen source during this period of rapid nitrogen accumulation. Similar to other northern Pacific Rim floodplains, we found that new alluvial deposits were colonized by Salix, Chosenia, and Alnus trees; but, unlike other described chronosequences, the community transitioned into meadows of tall forbs (some \u3e2.5 m in height) dominated by Filipendula camtschatica after 100 years. Foliage of all the major vascular plants occurring in the modern floodplain was exceptionally nitrogen rich (i.e., mean molar C:N for each species was 12–27, and the range for all samples was 8–36); therefore we suggest that salmon allow nitrophilic vegetation to proliferate in the Kol floodplain by ameliorating nitrogen infertility during early succession and building nitrogen rich soils